Nonvolatile memory devices are capable of persisting data for extended periods of time without needing to be powered to maintain such data storage. For example, information is written to a nonvolatile flash memory device by changing the electrical characteristics of transistor-based memory cells of the flash memory device to change how such memory cells react to applied voltages. The electrical characteristics of different memory cells in a semiconductor memory device are representative of binary bits that can be read by sensing threshold voltages of the memory cells in response to applied input voltages.
A nonvolatile memory device includes a matrix or array of memory cells. In some memory devices, each memory cell stores a single bit of data. In other memory devices, such as multi-level cell (MLC) memory devices, each memory cell stores multiple bits of data.
The figures are not to scale. Wherever possible, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts.